It is well known that people often enjoy sleeping in their seats while traveling in an airplane, train, automobile, or other mode of transportation. However, it is difficult for a person to sleep in his or her seat when the back portion of the seat is in an upright position or reclined position. Thus, it is difficult for a traveler to be comfortable when attempting to sleep, especially because a traveler's head is not stabilized while in an upright position. As a result, the traveler's head can fall forward during sleep.
Travelers often attempt to lean their heads against a stationary object such as a window, or rely on a pillow placed between the head and the back surface of the seat for comfort. However, when the head is not secured against the stationary object, the traveler's head is subject to abrupt movement during sleep.